1. Technical Field of the Invention
This invention relates to radio telecommunication systems and, more particularly, to a system and method for two-way in-flight radio telecommunications on board an aircraft.
2. Description of Related Art
Air-to-ground telecommunication systems on board aircraft are widely known and used. These in-flight systems typically provide a passenger with the ability to initiate a telephone call by contacting a ground-based station and connecting to the public switched telephone network (PSTN), and from there, to a called party.
However, existing in-flight telecommunication systems suffer from several disadvantages. First, a ground-based caller has no way of originating a call to a passenger on board an aircraft through an in-flight telephone system. Existing in-flight telephone systems do not permit incoming calls. The closest existing system to a two-way in-flight telephone system requires a ground-based caller to call a special airborne telephone number specific to an airborne passenger on a particular flight. The ground-based caller must input the ground-based telephone number where the call is being originated. If the airborne passenger has registered his location with the system, the airborne passenger receives a message indicating that the ground-based caller requests a call. The airborne party must then call back the ground-based caller.
Additionally, a passenger may not use his own mobile telephone on board an aircraft because the mobile telephone's radio frequency (RF) signal may interfere with aircraft operations. The passenger must use the telephone provided in the seat-back in front of him, and pay higher access fees associated with the existing in-flight system. Also, since the existing in-flight system does not allow the passenger to use his own mobile telephone, the passenger loses the benefits of many advanced features and services to which he may subscribe. Thus, when utilizing an existing in-flight telecommunication system, a passenger must pay higher fees while receiving less service than he obtains when using his own mobile telephone.
Although there are no known prior art teachings of a solution to the aforementioned deficiency and shortcoming such as that disclosed herein, prior art references that discuss subject matter that bears some relation to matters discussed herein are U.S. Pat. No. 5,278,891 to Bhagat et al. (Bhagat '891), U.S. Pat. No. 5,408,515 to Bhagat et al. (Bhagat '515), and U.S. Pat. No. 5,212,804 to Choate (Choate). Bhagat '891 discloses a ground-to-air telephone calling system for calling a subscriber on an aircraft with a single telephone. Specifically, the patent provides for a system for receiving a call while airborne in an aircraft. The system includes a ground-based computer for receiving a called airborne telephone number and a call-back number from an originating party on the ground. Bhagat '981 requires the originating party to input an Air-Ground Radiotelephone Automated Service (AGRAS) number, representing an identification number of the airborne telephone to be called. The originating party must then input a call-back number (i.e., his own telephone number) and then hang up. Subsequently, the system connects the two parties by calling the airborne party and then calling the originating party.
Thus, Bhagat '891 suffers from several disadvantages. This telephone system requires the originating party to enter an additional AGRAS number, as well as the originating party's own number. Furthermore, this system works with aircraft possessing only one airborne telephone, but not those aircraft possessing more than one telephone.
Bhagat '515 discloses a ground-to-air telephone calling system as discussed in Bhagat '891, but provides for ground-to-air calls to aircraft possessing more than one telephone. Bhagat '515 requires that an airborne subscriber be assigned and utilize a Traveler Assigned Number (TAN), which is associated with a particular seat on an airplane. Bhagat '515 suffers from the same disadvantages of Bhagat '891 associated with the requirements for the originating party to enter an AGRAS number, enter the originating party's own number, hang up, and wait for a call back from the system. Bhagat '515 then adds the additional complexity of requiring a TAN to be assigned to each passenger. This is a very burdensome task for airlines, and in any event, will not work on those airlines that do not assign specific seats to passengers.
Choate discloses an air-to-ground telephone system having multiple ground-based base stations and multiple airborne mobile units. Specifically, the patent provides for controlling multiple two-way radiotelephone conversations between a number of aircraft and a network of base stations capable of being interconnected to landline telephone networks. Choate, however, does not provide for ground-initiated calls to an airborne party.
It would be a distinct advantage to have a two-way in-flight telecommunication system and method of providing an airborne subscriber with the ability to originate and receive telephone calls in the aircraft at the subscriber's seat, such calls being made with subscribers on the ground or with other airborne subscribers. In addition, it would be advantageous for such a system to operate by utilizing the airborne subscriber's own mobile telephone without interfering with aircraft navigation or communication systems. It is an object of the present invention to provide such an in-flight telephone system and method.